The Heusler alloys are promising material for various applications, including thermoelectric power generators. There are several ways to improve their properties, among which the substitution of ...constituent elements, nanostructuring, temperature treatment, thin films engineering etc. This work is devoted to the experimental study of thermoelectric properties of Fe-V-Al-based Heusler alloys with different compositions under high pressure. The Seebeck coefficient and electrical resistance of several compounds were measured as a function of applied pressure up to 10 GPa at room temperature. The experimental results demonstrated a diversity of pressure responses of the thermoelectric properties that can be observed in chemically similar Heusler alloys under variation in their compositions. Moderate enhancing of the thermoelectric power factor, S
2
/r (where S is the Seebeck coefficient and r is the electrical resistivity) was observed in Fe-rich Fe
2.1
V
0.91
Al
0.99
compound at a pressure about ∼1 GPa. It was found that all alloys with weak deviation from stoichiometric composition had a feature in their S (P) pressure behavior at P∼2 GPa which could be related to semimetal-metal phase transition.
Angular analysis of the rare decay Bs0→ ϕμ+μ Ackernley, T.; Balagura, V.; Belyaev, I. ...
The journal of high energy physics,
11/2021, Letnik:
2021, Številka:
11
Journal Article
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A
bstract
An angular analysis of the rare decay
B
s
0
→ ϕμ
+
μ
−
is presented, using proton-proton collision data collected by the LHCb experiment at centre-of-mass energies of 7, 8 and 13 TeV, ...corresponding to an integrated luminosity of 8.4 fb
−
1
. The observables describing the angular distributions of the decay
B
s
0
→ ϕμ
+
μ
−
are determined in regions of
q
2
, the square of the dimuon invariant mass. The results are consistent with Standard Model predictions.
The article presents the experimental results concerning the role of cobalt impurities in low-temperature electrical conduction and in the Hall concentration of electrons in crystals of mercury ...selenide. In the limit of small concentrations of the impurities, a slow variation of the electron concentration was found as a function of impurity content, which can correspond to a donor character of the impurity
d
levels of cobalt atoms located in the conduction band of the host crystal under conditions of hybridization. Characteristic features have been observed in the concentration and temperature dependences of the electrical conductivity, similar to those that manifest themselves in crystals with hybridized states of iron impurities. As a result, the set of data obtained on crystals with cobalt impurities, including the previously published data on the concentration dependence of the Curie constant and on the temperature dependence of thermopower, can be used on a qualitative level as an experimental substantiation of the previously predicted existence of two donor hybridized electron states of a cobalt impurity atom in the conduction band.
In 1997, an H5N1 avian influenza A/Hong Kong/156/97 virus transmitted directly to humans and killed six of the 18 people infected. In 1999, another avian A/Hong/1074/99 (H9N2) virus caused influenza ...in two children. In such cases in which vaccines are unavailable, antiviral drugs are crucial for prophylaxis and therapy. Here we demonstrate the efficacy of the neuraminidase inhibitor GS4104 (oseltamivir phosphate) against these H5N1 and H9N2 viruses. GS4071 (the active metabolite of oseltamivir) inhibited viral replication in MDCK cells (EC
50 values, 7.5–12 μM) and neuraminidase activity (IC
50 values, 7.0–15 nM). When orally administered at doses of 1 and 10 mg/kg per day, GS4104 prevented death of mice infected with A/Hong Kong/156/97 (H5N1), mouse-adapted A/Quail/Hong Kong/G1/97 (H9N2), or human A/Hong Kong/1074/99 (H9N2) viruses and reduced virus titers in the lungs and prevented the spread of virus to the brain of mice infected with A/Hong Kong/156/97 (H5N1) and mouse-adapted A/Quail/Hong Kong/G1/97 (H9N2) viruses. When therapy was delayed until 36 h after exposure to the H5N1 virus, GS4104 was still effective and significantly increased the number of survivors as compared with control. Oral administration of GS4104 (0.1 mg/kg per day) in combination with rimantadine (1 mg/kg per day) reduced the number of deaths of mice infected with 100 MLD
50 of H9N2 virus and prevented the deaths of mice infected with 5 MLD
50 of virus. Thus, GS4104 is efficacious in treating infections caused by H5N1 and H9N2 influenza viruses in mice.
The given report is devoted to the study of anomalous Hall resistance of donor electron system of hybridized states of transition element impurities of low concentration in quantum oscillation ...regime. There presented theoretical description of predicted specific behaviors on the base of the ideas about thermodynamic anomalous Hall effect. In experiments on mercury selenide crystals with cobalt impurities of low concentration one revealed the quantum oscillations of anomalous contribution to the Hall resistance corresponding to the developed concepts.
•Study of quantum oscillations of anomalous Hall resistance of donor electron system.•Quantum oscillations detected in mercury selenide crystals with cobalt impurities.•The oscillations are periodic in the inverse magnetic field and have large amplitude.•Theory based on the concept of thermodynamic anomalous Hall effect is provided.
A
bstract
Measurements are reported of the central exclusive production of
J/ψ
and
ψ
(2
S
) mesons in
pp
collisions at a centre-of-mass energy of 13 TeV. Backgrounds are significantly reduced ...compared to previous measurements made at lower energies through the use of new forward shower counters. The products of the cross-sections and the branching fractions for the decays to dimuons, where both muons are within the pseudorapidity range 2
.
0
< η <
4
.
5, are measured to be
σ
J
/
ψ
→
μ
+
μ
−
=
435
±
18
±
11
±
17
p
b
σ
ψ
2
S
→
μ
+
μ
−
=
11.1
±
1.1
±
0.3
±
0.4
p
b
.
The first uncertainties are statistical, the second are systematic, and the third are due to the luminosity determination. The cross-sections are also measured differentially for meson rapidities between 2.0 and 4.5. Good agreement is observed with theoretical predictions. Photoproduction cross-sections are derived and compared to previous experiments, and a deviation from a pure power-law extrapolation of lower energy data is observed.